From the Rio 2016 Olympics to the Paris 2024 Olympics: Is there a risk of Dengue disease?

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Human exposure to pesticides and thyroid cancer: a worldwide systematic review of the literatures.

Thyroid cancer is considered as one of the most prevalent cancers in the world. Some pesticides can play a role as a potentially important risk factor in thyroid cancer by affecting thyroid morphology and thyroid hormone homeostasis. The aim of present study was to systematically review the available epidemiological evidence for human exposure to pesticides and thyroid cancer. Articles were searched in PubMed, Scopus and Web of Science by suitable keywords from January 2000 to May 2021. Standard techniques for systematic reviews were followed in the current study and results reported according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Based on the inclusion and exclusion criteria, finally seven studies including four cohort studies and three case-control studies were reviewed. Organochlorines (OCPs) in more cases, Organophosphates (OPs) and Carbamates insecticides, herbicides and fungicides were the studied pesticides. Inconsistent results were reported in the surveyed articles on the OCPs. Two articles on the Carbamates (Carbaryl and Mancozeb) showed consistently an inverse association between exposure and thyroid cancer. Increased risk of thyroid cancer due to the exposure to the Malathion was reported in one article on the OPs. Due to the limited current knowledge about the effect of pesticides on thyroid cancer in humans, human health policies must be implemented to control individual's exposure to chemicals through using of botanical pesticides in agricultural. Also, more studies must be done to fill this gap of knowledge.

Determination of the feeding behavior of Phlebotomus sergenti using multiplex PCR and tent-baited traps in a new focus of Anthroponotic Cutaneous Leishmaniasis in the southeast of Iran.

OBJECTIVES: This study aimed to determine feeding behaviors of Phlebotomus sergenti Parrot, in a new focus of Anthroponotic Cutaneous Leishmaniasis in Bam County, southeast Iran. METHODS: Two methods were used to determine the feeding behavior of Phlebotomus sergenti. In the first method, blood-fed sand flies were captured using a mouth aspirator in human and animal dwellings and consequently, blood meal identification was made using Multiplex PCR. The results were used for calculating Host Feeding Index (HFI) and Forage Ratio (FR) parameters. In the second method, human (Homo sapiens), goat (Capra aegagrus), cattle (Bos taurus), chicken (Gallus gallus) and dog (Canis lupus) were used as baits in tent-baited traps to determine the feeding behavior of Phlebotomus sergenti. RESULTS: Multiplex PCR analysis revealed that the most frequent blood in the stomack of sand flies' were from chicken, but the calculation of the FR revealed that this species prefers canine and poultary blood as meal. Human and animal tent-baited traps revealed that most Phlebotomus sergenti were attracted to chicken rather than the other hosts. CONCLUSIONS: Sand flies are attracted to animals for various reasons such as eating blood, mating on their bodies and laying eggs on their feces. Molecular methods are effective and accurate methods to determine the type of host that sandfly fed on, but they do not show host preferences. The results of the molecular analysis, along with the calculation of HFI and FR, can determine the preferred host of sand flies. The current study revealed that dogs, the secondary reservoir of ACL in Iran, is the first preferred host of Phlebotomus sergenti.

Investigation of health and ecological risk attributed to the soil heavy metals in Iran: Systematic review and meta-analysis.

The presence of heavy metals (HMs) in the soil can pose risks to human health via ingestion and dermal absorption. This systematic review and meta-analysis study focused on both of health and ecological risks attributed to the six HMs (As, Cd, Cr, Cu, Pb, Zn) in the soil of different Provinces of Iran. Articles were selected in the Web of Science and Scopus from 2000 to August 2021. The study was carried out according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guideline. Based on the inclusion and exclusion criteria, finally 32 studies were reviewed which the ranking of mean concentrations of the studied metals followed as: As > Zn > Cr > Pb > Cu > Cd. Mean concentration of Cd and As calculated via meta-analysis in the studied Provinces was found to be more than Iran's environment protection agency (EPA) guideline values. Other HMs met guideline values. A significant non-carcinogenic risk attributed to the As found in Kurdistan Province (hazard index, HI > 1). Furthermore, a significant carcinogenic health risk was found in Kurdistan and West Azerbaijan associated to As and in Fars, Khozestan and Khorasan-e-Razavi Provinces associated to Cd (ELCR >10-4). Concerning the impact on the ecosystem, Cd, As and Pb caused ecological risks in some areas of Iran (ecological risk, ER > 40 and potential ecological risk, PER >150). Hence, we can conclude that Cd and As are important heavy metals from the health aspect. Moreover, Cd, As and Pb must be considered from an ecological point of view. Therefore, control of the Cd, As and Pb release in the environment and remediation of polluted sites through novel approaches is recommended.

Species Composition and Spatial Distribution of Medically Important Scorpions in the Northern Part of Kerman Province, Iran.

Background: Kerman Province is one of the endemic foci of scorpionism in southeastern Iran. Totally 17 species are reported for Kerman Province fauna. The current study seeks to determine the fauna of medically important scorpions in northern parts of this province. Methods: A descriptive cross-sectional study was conducted from January 2019 to March 2021. The specimens were captured from different areas, by rock-rolling during day and using Ultraviolet light at night. The specimens were preserved in ethanol (80%) and then identified using reliable identification keys for scorpions. Results: Totally, 499 specimens were captured from eight cities in northern Kerman. In total, 11 species belonging to three families were identified. Buthacus sp. is reported for the first time from Kerman Province. Buthacus sp., Hottentotta cf. juliae, and Hottentotta cf. schach, were the lowest in frequency of occurrence, against Mesobuthus navidpouri as the highest frequency. Conclusion: The results of this study are useful for the preparation of regional or monovalent antivenom for the Razi Vaccine and Serum Research Institute. Additionally, the obtained data are useful for the effective planning of scorpion control programs in the northern parts of Kerman Province, Iran.

Baseline susceptibility of a wild strain of main vectors of leishmaniasis to WHO-recommended insecticides in southeastern Iran.

BACKGROUND: In Iran, both cutaneous leishmaniases (CL) and visceral leishmaniases (VL) are endemic, recording one of the 10 highest CL prevalence in the world. Parasites are transmitted by the bite of infected Phlebotomus sand fly females. Several sand fly species have been identified as vectors in the studied region of Kerman province. Residual spraying to control adult sand flies, is the only way to decrease the spreading of the diseases but, following control treatment against malaria vectors in endemic areas in Iran, resistance or tolerance to insecticides emerged in some sand fly species. The objective of this study was to survey insecticides susceptibility levels of 3 vector species in wild sand fly populations in different foci of the diseases in Kerman province. Ph. sergenti, and Ph. papatasi respectively vectors of anthroponotic and zoonotic cutaneous leishmaniases and for the first time Ph. alexandri one of the anthroponotic visceral leishmaniases vector were tested against: deltamethrin 0.05%, malathion 5%, dichloro-diphenyl-trichloroethane (DDT) 4%. MATERIALS AND METHODS: In leishmaniases endemic areas species specific sand fly sites were selected in Kerman province, and specimens were collected by manual aspirators at different time intervals during the spring and summer 2019. All the susceptibility tests were performed according to the WHO tube test recommended procedure. RESULTS: Twenty five blood-fed female sand flies from the region's prevalent species were used in each pooled test replicates. All wild specimens died within 60 min of exposure to DDT 4%, malathion 5%, and deltamethrin 0.05%, but the mortality rate for Ph. papatasi exposed to malathion and DDT was 91.6% and 66.6%, respectively. CONCLUSION: According to current study results, Ph. sergenti and Ph. alexandri are highly susceptible to all the evaluated insecticides in the study areas. However, Ph. papatasi was susceptible to deltamethrin (100% mortality), possibly resistant or tolerant to malathion (91.6% mortality), and confirmed to be resistant to DDT (66.6% mortality).

Prevalence and Spatial Distribution of Bed Bug, Cimex lectularius, Infestation in Southwest of Iran: GIS Approach.

BACKGROUND: The common bed bug, a nocturnal bloodsucking insect, is known as a human parasite and public health problem in the world. The prevalence and geographical dispersion of bed bug in Ahvaz City, southwest of Iran was measured. METHODS: Spatial distribution of Cimex lectularius was determined by surveying 520 houses in 62 areas of Ahvaz City in 2017. Some information like as infested points, the concern level of the residents and allergic reaction to the insect bite were registered in a form using the secondhand instrument. RESULTS: According to the spatial distribution map, of 62 areas, 27 of them are infested with bed bugs. Infestation is scattered throughout the city, but its focus is on the east of the Karun River. The most bed bug infestation was in Asiabad followed by Manbaab areas. Prevalence of bed bug infestation estimated 9.61% in Ahvaz city. It was 5.4% and 11.6% in apartments and single houses, respectively. The lowest and highest infestation rates based on its source were 1.35% and 9.03% in wallpaper and cracks and crevices, respectively. Bedroom and sitting room were the main harborages for bed bug in the houses. The majority of residents who had bitten by a bed bug showed various allergic reactions like redness skin, papules, vesicles, pustules and blisters. Most of the people in the infested houses (62%) were very concern about bed bug infestation. CONCLUSION: Public education and increasing the knowledge of people can lead to successful management, prevention and elimination of this nuisance pest.

Effects of Resident Education and Self-Implementation of Integrated Pest Management Strategy for Eliminating Bed Bug Infestation in Ahvaz City, Southwestern Iran.

BACKGROUND: Bed bugs as blood-sucking insects have become a public health problem in urban communities throughout the world. The objective of this study was to determine the effects of resident education and self-implementation of Integrated Pest Management (IPM) strategy for eliminating bed bug infestation in infected apartments in Ahvaz City, Iran. METHODS: This interventional study was conducted in seventy apartments infested with bed bug (Cimex lectularius) in Ahvaz City, southwest Iran, during a 6-month period. The bed bug infestations reported to Health centers were inspected visually and confirmed by medical entomology experts. Then, the heads of the households were received techniques/tools of the IPM program and trained by medical entomology experts before self-implementation of control methods. Finally, the infected apartments were inspected by the experts at 1, 3, and 6 months after intervention and data were recorded in a checklist. RESULTS: From the seventy infected apartments, 57%, 28% and 15% were considered as low, moderate, and high level infestation respectively. The bed bug infestation was eliminated from 53 apartments (76%) after one month and it reached to 62 apartments (88%) by the end of third month. Finally, after six months of applying IPM program, bed bugs infestation was eliminated from all infected apartments (100%). Residents expressed their 100% satisfaction with applying the bed bug IPM strategy. CONCLUSION: Training residents to implement the IPM program can reduce pest control costs, the volume of pesticides consumed, and human exposure to chemical pesticides, resulting in increased human and environmental health and safety.

Chemical Composition and Repellency of Origanum vulgare Essential Oil against Cimex lectularius under Laboratory Conditions.

BACKGROUND: The common bed bug (Cimex lectularius), a nocturnal blood-feeding ectoparasite, is considered an urban pest with public health importance in human environments. We aimed to determine the repellency effect of oregano essential oil, Origanum vulgare, against this pest under laboratory conditions. METHODS: The essential oil was prepared from dried leaves using hydro-distillation method. A gas chromatography-mass spectrometer (GC-MS) was used for analysis and identification of oregano essential oil compounds. Treated surface method in Petri dish was carried out to evaluate repellency potential of the oil using 4th and 5th instar nymphs and adults. The concentration-repellency response of oregano essential oil was calculated and compared with a commercial insect repellent stick containing 33% N, N-diethyl-meta-toluamide (DEET). RESULTS: The oregano essential oil consisted of 158 compounds with terpineol (22.85%) and α-terpinene (20.60%) being the major components by volume. The EC50 and EC99 of oregano oil (effective concentrations causing 50% and 90% repellency of bed bugs) were 1.61 and 6.57mg/cm2 at 9h after application, respectively. The 40% oregano essential oil exhibited 100% repellency against bed bug at 3, 5, 9 and 24h after application while the repellency index of DEET 33% was 100% at 3 and 5h and it decreased to 80% and 27% at 9 and 24 hours. CONCLUSION: Oregano oil 40% exhibited more repellency compared to commercial insect repellent stick containing 33% DEET. Further studies are warranted to confirm the effectiveness of oregano essential oil in personal protecting against bed bug biting.